Pre-heat the oven to 160C fan-forced and grease and line a 24cm spring-form tin.

Place the butter and sugar in the bowl of a food processor and process until smooth.

Scrape down the sides then add the eggs, with the motor running, one at a time.

Add the vanilla and pulse it through then scrape down the sides again.

Add the flour and process for 1 minute.

Scrape down the sides then process for another 30 seconds.

Remove half the batter from the food processor.

Add the cocoa to the food processor and process for another 30 seconds then scrape dow the sides and repeat.

Starting with a blob of icing in the middle of the cake tin, spoon one blob of white cake batter and then top with a blob of chocolate batter (blob is about a tablespoon).

Keep alternating until you have used all the batter.

Bake the cake for 50 minutes to 1 hour or until a cake tester inserted in the middle comes out clean.

Leave the cake to rest in the tin for 10 minutes and then transfer to a wire rack to cool completely.

Beat the butter in the bowl of an electric mixer until light and fluffy.

Slowly add the icing sugar and cocoa and mix then in.

Add water a little at a time to get the icing to a spreadable consistency and beat until fluffy.

Pour some icing sugar onto a plate and roll the outside of the cake in it to coat.

Spread the icing on the top of the cake and top with Easter eggs.